Catholic Church officials are seeking to remove a former Benedictine monk and deacon from the clergy because they have deemed credible an accusation that he assaulted an 18-year-old Delbarton School alumnus on campus in 1981.

The Paterson Diocese initiated efforts to laicize Robert Flavin, 54, three months ago, asking him to seek his own formal dismissal from the clergy, according to diocese spokeswoman Marianna Thompson.

Flavin did not respond to the request and the diocese is gathering documents to send to the Vatican seeking a decree of laicization without his cooperation, Thompson said. A resolution could take months.

Flavin, who now lives in eastern Pennsylvania, has denied the accusations. Officials with the diocese and Delbarton, a school for grades 7-12 operated by Benedictine monks of St. Mary's Abbey in Morristown, said he had also refused to cooperate with their investigation.

"To respond is to acknowledge that there's some merit in the allegation, and he's not going to do that. He denies it," said William Ware, Flavin's lawyer.

Ware contends that Flavin is caught up "in the fervent groundswell to try to implicate anyone who's involved in religion these days."

Flavin's accuser, Bob Sheridan, 40, sees the move to laicize the former monk as validation.

"I feel fantastic right now," said Sheridan, a former Delbarton sports captain and a longtime fund- raiser for the exclusive Catholic school.

"It's my school, and I want to . . . prevent this from happening to some other kids. I did the community a distinctive service. His corrupt and despicable ministry is now over."

Sheridan, a software salesman, contends Flavin molested him in 1981 in an abbey cafeteria shortly after he graduated, and that Flavin said inappropriate things to him in the late 1970s while Sheridan was a student.

In May, the abbey's review board sent Sheridan a letter saying it had deemed the 1981 charge credible but had found insufficient evidence to support the allegation from the 1970s.

Morris County prosecutors decided in the spring they could not prosecute the case, said Assistant Prosecutor Joseph Redden. He said his office did not pursue many recently reported clergy sex-abuse accusations because of expired statutes of limitation.

Delbarton officials concede they should have responded differently when Sheridan told them in 1992 that Flavin had assaulted him years earlier.

Flavin, who had left the abbey in 1987 after 13 years there, was banned from returning to campus, said Delbarton spokesman Anthony Cicatiello. But the school did not inform the Paterson Diocese, where Flavin was then a deacon at Church of the Resurrection in Randolph.

"What everybody readily admits is they should've acted a little more promptly with the diocese in letting them know what we knew when we knew it," Cicatiello said. "What happened with the church (since last year) opened a lot of people's eyes."

Not until 2001 did Sheridan learn Flavin had been deacon for most of the 1990s at Church of the Resurrection, where, among other duties, he preached about twice a month. Sheridan complained to school officials, the church's pastor and the Paterson Diocese.

The Rev. John Andrew Connell, who has been at Resurrection Church for two years, said he did not know Flavin but has heard he was "very well-liked and delivered good homilies."

In July 2002, a lawyer who no longer represents Sheridan suggested he ask the school for a $600,000 settlement, Sheridan said.

Sheridan said he had been advised by the school to get an attorney.

The abbey, whose monks take poverty vows, declined to settle for that amount, though the current abbot, the Rev. Thomas Confroy, a military veteran, wrote Sheridan a personal check for $2,370 to help with counseling and bills, Cicatiello said.

Sheridan, who said he returned the check uncashed, said he was disturbed by the abbey's response and that he was treated rudely.

If Flavin is laicized, he would be the second in the Paterson Diocese since the national clergy sex scandal in 2002.

James Hanley, a former diocesan priest at St. Joseph's in Mendham, voluntarily requested laicization last year after several abuse complaints against him became public. Four other diocesan priests accused of charges that were deemed credible by the diocese await results of church investigations.